Overall, juvenile crime is down 37 percent in Massachusetts from 2009 to 2011, according to a recent report by Citizens for Juvenile Justice, a research and advocacy group in Boston. The drop corresponds with data in the FBI’s nationwide crime reports that show that crime is down in all categories across the country.

“In Brockton District Court, we had 709 juvenile cases in 2010. This year to date, it’s 431. In Hingham District Court, we saw 255 juvenile cases. This year to date it’s 150,” Plymouth District Attorney Timothy Cruz said.

Similarly, in neighboring Bristol County, the district attorney’s office prosecuted 988 juveniles in 2012, down nearly 28 percent from 2010 when it prosecuted 1,370, according to spokesman Gregg Miliote. Norfolk County tried 1,260 juvenile cases in 2010 and 1,182 in 2012, according to the Massachusetts Trial Court system’s website.

For the purposes of the Citizens for Juvenile Justice study, which includes FBI crime data and covered juvenile arrests for all kinds of crimes, a juvenile is anyone under the age of 18, although some older teens are tried as adults. About 89 percent of the Massachusetts juveniles arrested in 2010 were charged with nonviolent offenses, according to the group’s report.

Local law enforcement officials say they are pleased with the reduction in juvenile crime, but they also point out there is more work to be done. While it’s difficult to tie the drop in crime to any specific initiative, officials in some communities south of Boston agree that efforts in early intervention and matching at-risk youngsters to the services they need are paying off.

“There’s a variety of reasons” why juvenile crime is down, said Cruz. “One of them is our post-arrest diversion programs. These programs give kids the option to do things like community service instead of going to court and risking a criminal conviction.” Cruz also credited other educational and intervention programs run by each prosecutor’s office.

“There’s an increased awareness among both students and parents about the dangers of underage drinking, social host responsibility, and bullying,” he said. “I think that at the end of the day people are learning that there are other ways to treat kids who have committed transgressions against the law.”

Norfolk District Attorney Michael Morrissey agrees. “Juvenile court is a great setting to deal with some of the younger kids, but the goal of diversion programs is trying not to give juveniles criminal records,” he said. The Citizens for Juvenile Justice report shows that the majority of juveniles arrested are between 13 and 16 years old. Also, while girls still make up a minority of youngsters in Department of Youth Services custody, their numbers are growing. In 2011, 30 percent of the youngsters arrested in Massachusetts were girls.

Morrissey cited early intervention as one important factor in lowering the juvenile crime rate, saying, “All of the DAs spend a lot of time doing education, prevention, and intervention.”

Cruz and Morrissey said the decriminalization of possession of small amounts of marijuana in 2008 also has decreased the number of juvenile arrests in the Commonwealth.

There are other theories for the drop that are harder to appraise. Cruz said one of his colleagues suggested that the drop could also have something to do with the fact that MCAS testing forces teachers and schools to focus on and help troubled students earlier because schools are penalized for low test scores.

Randolph police Detective Gabriel Pantazelos, who has worked in the town’s public schools for five years, said that while crime is down, it remains a problem.

In 2007, the year he started working in the schools, Randolph police arrested 106 juveniles. That number has dropped steadily through the years; in 2010, Randolph police arrested 58 juveniles.

“It’s been a much quieter year from last year, but kids are impulsive,” said Pantazelos. “Recently we had a kid snatch a cellphone from a teacher’s desk. To have the ability to bring him to a probable cause hearing rather than cuff him — that’s preferable.”

Pantazelos credited “more resources and more collaboration, more early intervention, bullying awareness, and early education” for the downward trend in juvenile crime rates. He meets monthly with other agencies to discuss how better to collaborate resources.

“We have very strong partnerships between school, police, probation, but parental engagement is huge,” he said. “We’re a team, local law enforcement, parents, schools, social workers, other agencies. . . . It takes a village. I check in with my regional DYS guy two, three, times a week.

“We’ve learned a lot about what works and what doesn’t, and our chief is committed to keeping kids and the community safe. It’s not about handcuffs, it’s about keeping kids on the right path.”

Crystal Collier, director of operations for the Department of Youth Services’ central region, said she has also seen a reduction in the number of juveniles in the DYS system and believes it is the result of preventative work being done by agencies across the state.

The numbers bear it out. In 2002, the DYS census showed 3,300 youngsters in the system under the age of 18. By 2009, that number was 1,637, and in 2011, it was 1,288.

“There’s a lot of good work being done on the front end,” Collier said. “Department of Children and Families, schools, probation, and juvenile court all work to try to provide kids with the appropriate services to keep them out of detention.”

Collier singled out the Juvenile Detention Alternatives Initiative as a major factor. The initiative has been active in Massachusetts since 2006, trying to match youths with the services they need.

“We’re thinking about, is jail the right place for this kid? What are their risks? What’s driving this behavior? If we can catch and identify issues early enough, we can prevent the snowball effect,” she said.

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